Safety belt D-ring positioning

ABSTRACT

Guidance to a vehicle occupant is directed to manual adjustment of a height of a D-ring mechanism of a safety belt. First data of the occupant is collected which is indicative of a target height for the D-ring mechanism. Second data is collected indicative of a current height of the D-ring mechanism. The target height and the current height are compared to generate an adjustment amount whenever their difference is greater than a predetermined threshold. Visual guidance is presented to the occupant on an HMI display panel wherein the visual guidance describes taking an particular action to achieve the manual height adjustment of the D-ring mechanism. A further visual instruction is presented to the occupant on the HMI display panel wherein the visual instruction identifies the adjustment amount.

CROSS REFERENCE TO RELATED APPLICATIONS

Not Applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable.

BACKGROUND OF THE INVENTION

The present invention relates in general to adjustable safety beltrestraints in motor vehicles, and, more specifically, to a help systemfor configuring an optimal height of a safety belt over a shoulder of avehicle occupant.

Passenger seats in motor vehicles typically have adjustable positions tomove forward, rearward, upward, and downward for optimal positioningrelative to the controls, windows, and interior trim of the vehicle andfor optimal passenger comfort. Seat position adjustments may be manualor powered. Powered seats (especially the driver seat and frontpassenger seat) may have customizable memory settings, so that optimizedpositions may be automatically restored for frequent users.

Front row seats often have a 3-point safety belt system to retainoccupants in the seats. A seat belt webbing may have a lower end fixedto the vehicle (e.g., bolted near the floor of the passenger compartmenton an outboard side of the seat). The webbing carries a slidable clipwhich selectably connects with a buckle attached to an inboard side ofthe seat. Above the clip, the belt webbing passes through a D-ringmechanism which is usually located on a pillar of the vehicle. Afterpassing through the D-ring, the other end of the seat belt webbing maybe engaged with a retractor that feeds out a variable length of beltwebbing as needed to restrain the seat occupant.

The D-ring mounted to the pillar of the vehicle (e.g., the B pillar)supports the seat belt at the shoulder level of the occupant. The seatbelt shoulder strap should ideally cross over the mid-shoulder area(i.e., not too close to the neck and not too close to the arm). If theshoulder strap lays on the arm or neck, it may be uncomfortable for theoccupant and less effective in performing its restraint function. Thus,a target location for the shoulder strap is between the shoulder andneck.

When buckled, the seat belt webbing crosses over the occupant from thebuckle up to the D-ring. The placement of the webbing in the area of theshoulder depends on the height of the D-ring and the position of theoccupant's shoulder. In turn, the position of the occupant's shoulderdepends on their body height and shape and on the adjusted positioningof the seat. For example, changes in seat position will affect the wherethe shoulder strap lays on the occupant.

In order to properly position the D-ring mechanism relative to the seatoccupant, the D-ring height may be made vertically adjustable along thepillar to accommodate varying shoulder heights of different occupants. Amotor or other actuator can be coupled with the D-ring mechanism toprovide an automatic or powered adjustment system. An automatic systemis disclosed in U.S. Pat. No. 10,035,513, entitled “Seat Belt HeightSystem and Method,” which is incorporated herein by reference in itsentirety. However, most commercially available vehicles use manuallyadjustable D-ring mechanisms. An example of a manually adjustable D-ringis shown in U.S. Pat. No. 10,981,537, entitled “Seatbelt HeightAdjuster,” which is incorporated herein by reference in its entirety. Ina manually adjustable system, a mechanical locking feature may beprovided which must first be released before being able to change theheight of the D-ring along the pillar.

In practice, occupants may not always adjust the height of the D-ringinto an optimal position due to many reasons, such as 1) the D-ring isout of sight of the occupant, 2) the occupant is unaware that theposition of the D-ring affects operation of the seat belt, 3) theoccupant is busy and chooses not to take the time to adjust the D-ring,and/or 4) the occupant is unaware that a previous occupant changed theposition of the D-ring.

The use of stored seat positions in a personalization memory forparticular occupants/driver/passengers typically involves an automaticidentification of a person accessing the vehicle (e.g., by identifying adedicated key or by image recognition). While seat position and otherpersonalization settings have been stored in memory, a D-ring height hasnot been included in personalization settings. Whenever the seatmemory/personalization position is changed for different users accessingthe vehicle, manually changing the position of the D-ring is usuallyrequired. However, many people do not know that the D-ring can beadjusted, resulting in reduced comfort and effectiveness.

SUMMARY OF THE INVENTION

Using interior camera(s) and/or interior sensing technology, differencesbetween a target D-ring height and an actual height can be determined,and a vehicle occupant can be notified to perform a manual adjustmentwhenever needed.

In one aspect of the invention, a vehicle comprises a safety belt systemfor a front seat occupant having a belt webbing passing through a D-ringmechanism, wherein the D-ring mechanism has a manually adjustableheight. A sensing system is configured to detect the front seat occupantand to collect A) first data of the front seat occupant indicative of atarget height for the D-ring mechanism, and B) second data indicative ofa current height of the D-ring mechanism. A controller is coupled to thesensing system and configured to 1) determine the target height inresponse to the collected first data, 2) determine the current height inresponse to the second data, and 3) compare the target height to thecurrent height to generate an adjustment amount if a difference betweenthe target height and the current height is greater than a predeterminedthreshold. An HMI display panel which is responsive to the controllerpresents to the front seat occupant A) a visual guidance describing anaction to achieve the manual height adjustment of the D-ring mechanism,and B) a visual instruction identifying the adjustment amount.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a vehicle having a driver in a driver's seatand wearing a 3-point safety belt system.

FIG. 2 is a perspective view of a first embodiment of an adjustableD-ring mechanism on a B-pillar.

FIGS. 3 and 4 are perspective views of a second embodiment of anadjustable D-ring mechanism showing the D-ring mechanism at differentheights.

FIG. 5 is a side view of a driver's seat and a driver/occupant togetherwith a B-pillar D-ring mechanism and image sensors for detecting heightsof the D-ring and predetermined anatomical features of the occupant.

FIG. 6 is a block diagram showing a vehicle and a safety belt systemaccording to a preferred embodiment.

FIG. 7 is a flowchart showing one preferred method of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 1, a motor vehicle 10 has a passenger compartment 11with a front seat 12 holding a driver/occupant 13. A 3-point safety beltsystem includes a belt webbing 14 which clips to a seat buckle 15 at anintermediate location and which passes through a D-ring mechanism 16mounted at a B pillar 17. To achieve an optimal orientation of webbing14 at a shoulder of occupant 13, D-ring mechanism 16 has an adjustableheight so that it can maintain a desired relative height with respect tothe shoulder of occupant 13.

Passenger compartment 11 may include one or more image sensors 18 (e.g.,cameras) which are configured to capture data (e.g., images) to supportdetection of a height of a predetermined reference anatomy of occupant13 (e.g., a shoulder or another feature from which a shoulder height canbe inferred). Other sensors such as seat position sensors, ultrasonicsensors, and/or radar sensors, and other identification devices such askey fobs, ID cards, or transponders may used instead of or incombination with image sensors to characterize an identity and/or ashoulder height of an occupant.

FIG. 2 shows a first D-ring mechanism 20 on a B pillar 21. A beltwebbing 22 carrying a clip 23 passes through D-ring 20 and extends downto a retractor (not shown) contained behind B pillar 21. By depressing alock button 24 on D-ring mechanism 20, a user can raise or lower D-ringmechanism 20 along a vertical height adjustment range. A trim piece 26is fixed to D-ring mechanism 20 and slides along with D-ring mechanism20 to conceal an opening which accommodates D-ring mechanism 20 therein.

FIGS. 3 and 4 show another safety belt system with a D-ring mechanism 30mounted at a B pillar 31. A D-ring 32 has a slot for passing through abelt webbing 33. A handle 34 includes a release button 35 which can bepressed by a user in order to raise or lower a height of D-ring 32. Asliding panel 36 associated with D-ring mechanism 30 provides a screenconcealing an interior of B pillar 31 which could otherwise be visiblethrough an opening in B pillar 31. A height of D-ring mechanism 30 canbe measured relative to any fixed feature. Using an upper edge 37 of theopening in B pillar 31 may be selected to simplify image processingwhich may be used to determine D-ring actual height. For example, FIG. 3depicts D-ring mechanism 31 at a first height which is a distance D1below edge 37, and FIG. 4 depicts D-ring mechanism 31 at a second heightwhich is a distance D2 below edge 37. Alternatively, a displacementsensor could be incorporated into D-ring mechanism 30 to directly sensethe height.

To determine an optimal placement of a D-ring height relative to aparticular occupant (e.g., driver or passenger) in a front seatlocation, a direct measurement or a measurement-based estimate of thecurrent heights of the D-ring and of the shoulder of the occupant aredesired. In some embodiments, if the identity of an occupant is knownthen a previously obtained measurement may be obtained from a memory asa stored value. FIG. 5 depicts optical measurements of the D-ring and/oroccupant heights. An image sensor 40 is mounted at a reference positionin passenger compartment 41 and has a field of view covering at least aportion of an occupant 42 and a D-ring mechanism 43. Image sensor 40 maybe comprised of a CCD camera or a CMOS camera, for example, and may beconfigured for visible light and/or infrared detection. An imageprocessor (not shown) may inspect images from image sensor 40 using wellknown methods to detect predetermined image elements such as 1) theshoulder of the occupant or another reference anatomy (e.g., the eyes)which can be correlated to the level of the shoulder, and/or 2) areference location on D-ring mechanism 43. The image processor mayutilize pattern recognition, for example. The inspected image mayinclude a height reference, such as an imaginary horizontal referenceline corresponding to a horizontal line or plane 46 within passengercabin 41 which corresponds to a known location in captured images due toimage sensor 40 being installed at a reference position and apredetermined orientation.

FIG. 5 depicts a vector 44 corresponding to a detected location of theoccupant's eyes in the inspected image which lies at an angularseparation 47 from horizontal plane 46. Based on a distance from sensor40 to the occupant's eyes, the height of the occupant' s eyes can bedetermined. The sensor-to-occupant distance can be determined using asensor (e.g., a time-of-flight sensor or other sensor incorporated withsensor 40) or based on an adjusted seat position, for example. An eyeheight can be converted to a shoulder height based on anthropometricdata as explained in U.S. Pat. No. 10,035,513. Likewise, a height ofD-ring mechanism 43 can be determined using an angular separation of avector 45 pointing toward D-ring 43 and horizontal plane 46 and using aknown distance from image sensor 40 to D-ring 43. Alternatively, aheight of D-ring mechanism 43 can be measured according to an outputfrom a displacement sensor 50 which may be incorporated with D-ringmechanism 43.

FIG. 6 provides a block diagram showing main elements of amonitoring/notification system 51 for detecting an out-of-positionD-ring mechanism and generating a notification and adjustmentinstructions to a vehicle occupant. A controller 52 may be aprogrammable electronic module which is configured to perform functionsas described herein together with other vehicle control functions.Controller 52 has a memory 67 for storing data such as personalidentifiers and associated target heights as determined for specificoccupants. Controller 52 may be implemented within a main body controlmodule, a driver information or infotainment module or a restraintscontrol module, or it may be distributed over a plurality of such units.Controller 52 communicates with other devices using one or more wired orwireless communication links such as communication bus segments 53 and57. The bus or buses may be comprised of a CAN bus, for example.Controller 52 is coupled by bus segment 53 to in-vehicle image sensors54 and 55 which are arranged to capture images which may include thefront seat occupant(s) and D-ring mechanism(s). Controller 52 is coupledby bus segment 57 to additional modules 58 and to additional sensors 56such as seat position sensors or a D-ring displacement sensor. Modules58 are coupled to other sensors and may relay sensor signals and/orother information (e.g., passenger identification data) to controller52.

The cameras 54 and 55, sensors 56 and 59, and other modules 58 coupledto controller 52 provide a sensing system which is configured to detectthe presence of a front seat occupant and to collect first data of thefront seat occupant indicative of a target height for the D-ringmechanism, and second data indicative of a current height of the D-ringmechanism. The first data may include a captured image at leastpartially depicting the front seat occupant (which can be input to apattern recognition analyzer to identify a location in the capturedimage of a reference anatomy of the front seat occupant, and thendetermines the target height for the D-ring mechanism according to arelation between the identified location and a shoulder location of thefront seat passenger). The first data may include a stored personalidentifier uniquely assigned to the front seat occupant and a respectivestored target height previously determined by the sensing system.Alternatively, the first data can comprise a seat adjustment parameterwithin an available range of seat adjustment (e.g., to specify a camerato occupant distance). The second data may include a captured image atleast partially depicting the D-ring mechanism of may comprise of anoutput of a displacement sensor.

Controller 52 determines the target height in response to the collectedfirst data, determines the current height in response to the seconddata, and compares the target height to the current height to generatean adjustment amount if a difference between the target height and thecurrent height is greater than a predetermined threshold.

A human machine interface (HMI) 60 is coupled to controller 52 via bussegment 57. HMI 60 includes a display panel 61 for providing graphicimages and textual messages to the occupants and a sound transducer 65(e.g., a speaker) for providing audible tones or messages. When a neededadjustment of D-ring height is determined using the procedures describedherein, display panel 61 is used to present appropriate feedback to thefront seat occupant(s) as assistance in obtaining a recommended D-ringheight. The feedback may preferably be comprised of A) a visual guidancedescribing an action to achieve the manual height adjustment of theD-ring mechanism, and B) a visual instruction identifying the adjustmentamount. As shown in FIG. 6, a graphic image 62 of the D-ring mechanismmay be displayed along with a description 63 of an action to beperformed in order to release the D-ring mechanism for adjustment (e.g.,pressing a button on the mechanism and sliding the mechanism up ordown). When an adjustment is needed, speaker 65 may be activated toreproduce a chime or other alerting sound to get the attention of theoccupant(s).

Controller 52 may be further configured to monitor the second data aftera manual adjustment of the D-ring mechanism to a modified height,compare the target height to the modified height, generate a new visualinstruction identifying a new adjustment amount on the HMI display panelif a difference between the target height and the modified height isgreater than the predetermined threshold, and generate a confirmationmessage on the HMI display panel if the difference between the targetheight and the modified height is less than the predetermined threshold.Controller 52 can store a personal identifier of the respective frontseat occupant in association with the target height in a memory if theoccupant is identifiable in the future and is not already represented inthe stored data.

FIG. 7 shows one preferred method of the invention which begins at step70 when one or more occupants become seated in seats having acorresponding safety belt extending through an adjustable-height D-ringmechanism. The vehicle is started by the driver in step 71. A check isperformed in step 72 to determine whether any of the occupants in therelevant seating locations (e.g., front seats) have been identified as aspecific user and have previously stored data (e.g., a target D-ringheight or reference anatomy data) that can be used in determining theneed for and/or amount of D-ring height adjustment. If a personalidentifier associated with the identified user is found in memory, thena stored height (e.g., target D-ring height or height of the user) isrecalled in step 54. If there is no personal identifier associated withthe seat occupant, then sensor data (e.g., captured images, seatposition, etc.) is evaluated in step 73 to determine various heightssuch as the actual height of the D-ring mechanism and the actual heightof the shoulder (or other related anatomy) of the occupant, which can beused to determine a target height for the D-ring mechanism thatoptimizes comfort and effectiveness of the safety belt for the occupant.

In step 75, the target height of the D-ring is compared to the currentactual height of the D-ring in order to determine whether any adjustmentis needed.

Preferably, the comparison generates an adjustment amount whenever adifference between the target height and the current height is greaterthan a predetermined threshold. Differences less than the threshold maybe ignored. The threshold may be about 0.5 inches, for example. Theadjustment amount may be comprised of the difference between the targetheight and the current height, but the amount may be limited accordingto the ends of the movement range of the D-ring mechanism.

If an adjustment is needed, then an audible chime or other alerting toneor message may be generated as an audible cue in step 76 along with acorresponding message on the HMI display panel to inform an occupantthat action needs to be taken in order to properly adjust their D-ringheight. In step 77, the HMI display panel reproduces a visual guidancewhich describes/illustrates the action(s) which enables a verticalheight adjustment of the D-ring mechanism. In step 78, the HMI displaypanel further reproduces a visual instruction which identifies theadjustment amount. In step 80, a re-check can be optionally performedwhich includes recapturing camera images or other sensor data todetermine the current actual height of the D-ring mechanism has beenadjusted to the proper height (e.g., within the predetermined thresholdaround the target height). If still not at a proper height, then areturn can be made to steps 77 and 78, with the value of the adjustmentamount updated in the event that the D-ring mechanism has been moved bysome amount.

If a proper position is detected in step 80 or if no adjustment wasneeded in step 75, then an HMI confirmation message may be shown in step81 as an acknowledgement to the occupant(s) that the D-ring mechanism isset at an optimal height. If a new identifiable person is detected to bein the seat, then corresponding data including a personal identifier andthe target height for the D-ring based on the detected size of theoccupant can be stored together in a memory for later recall when thesame person sits in the same seat.

What is claimed is:
 1. A vehicle comprising: a safety belt system for afront seat occupant having a belt webbing passing through a D-ringmechanism, wherein the D-ring mechanism has a manually adjustableheight; a sensing system configured to detect the front seat occupantand to collect A) first data of the front seat occupant indicative of atarget height for the D-ring mechanism, and B) second data indicative ofa current height of the D-ring mechanism; a controller coupled to thesensing system and configured to 1) determine the target height inresponse to the collected first data, 2) determine the current height inresponse to the second data, and 3) compare the target height to thecurrent height to generate an adjustment amount if a difference betweenthe target height and the current height is greater than a predeterminedthreshold; and an HMI display panel responsive to the controller topresent to the front seat occupant A) a visual guidance describing anaction to achieve the manual height adjustment of the D-ring mechanism,and B) a visual instruction identifying the adjustment amount.
 2. Thevehicle of claim 1 wherein the controller is further configured to 4)monitor the second data after a manual adjustment of the D-ringmechanism to a modified height, 5) compare the target height to themodified height, 6) generate a new visual instruction identifying a newadjustment amount on the HMI display panel if a difference between thetarget height and the modified height is greater than the predeterminedthreshold, and 7) generate a confirmation message on the HMI displaypanel if the difference between the target height and the modifiedheight is less than the predetermined threshold.
 3. The vehicle of claim2 wherein the controller is further configured to 8) store a personalidentifier of the respective front seat occupant in association with thetarget height in a memory.
 4. The vehicle of claim 1 wherein the sensingsystem comprises an image sensor located at a reference position, andwherein the first data is comprised of a captured image at leastpartially depicting the front seat occupant.
 5. The vehicle of claim 4wherein the controller is configured to 8) use pattern recognition toidentify a location in the captured image of a reference anatomy of thefront seat occupant, and 9) determine the target height for the D-ringmechanism according to a relation between the identified location and ashoulder location of the front seat occupant.
 6. The vehicle of claim 1wherein the first data comprises a stored personal identifier uniquelyassigned to the front seat occupant and a respective stored targetheight previously determined by the sensing system.
 7. The vehicle ofclaim 1 wherein the first data comprises a seat adjustment parameterwithin an available range of seat adjustment.
 8. The vehicle of claim 1wherein the sensing system comprises an image sensor located at areference position, and wherein the second data is comprised of acaptured image at least partially depicting the D-ring mechanism.
 9. Thevehicle of claim 1 wherein the sensing system comprises a displacementsensor coupled to the D-ring mechanism, and wherein the second data iscomprised of an output of the displacement sensor.
 10. The vehicle ofclaim 1 wherein the visual guidance is comprised of a graphic depictionof an action to release the D-ring mechanism for movement.
 11. Thevehicle of claim 1 further comprising a sound transducer coupled to thecontroller for generating an audible cue to the front seat occupant whena manual adjustment of the D-ring mechanism is needed.
 12. A method ofguiding a front seat occupant of a vehicle to manually adjust a heightof a D-ring mechanism of a safety belt, comprising the steps of:collecting first data of the front seat occupant indicative of a targetheight for the D-ring mechanism; collecting second data indicative of acurrent height of the D-ring mechanism; determining the target height inresponse to the collected first data; determining the current height inresponse to the second data; comparing the target height to the currentheight to generate an adjustment amount if a difference between thetarget height and the current height is greater than a predeterminedthreshold; presenting a visual guidance to the front seat occupant on anHMI display panel wherein the visual guidance describes taking an actionto achieve the manual height adjustment of the D-ring mechanism; andpresenting a visual instruction to the front seat occupant on the HMIdisplay panel wherein the visual instruction identifies the adjustmentamount.
 13. The method of claim 12 further comprising the steps of:monitoring the second data after a manual adjustment of the D-ringmechanism to a modified height; comparing the target height to themodified height; generating a new visual instruction identifying a newadjustment amount on the HMI display panel if a difference between thetarget height and the modified height is greater than the predeterminedthreshold; and generating a confirmation message on the HMI displaypanel if the difference between the target height and the modifiedheight is less than the predetermined threshold.
 14. The method of claim13 further comprising the step of storing a personal identifier of therespective front seat occupant in association with the target height ina memory.
 15. The method of claim 12 wherein the step of collectingfirst data is comprised of capturing an image at least partiallydepicting the front seat occupant using an image sensor located at areference position in the vehicle.
 16. The method of claim 15 furthercomprising the steps of: using pattern recognition to identify alocation in the image of a reference anatomy of the front seat occupant;and determining the target height for the D-ring mechanism according toa relation between the identified location and a shoulder location ofthe front seat occupant.
 17. The method of claim 12 wherein the firstdata comprises a stored personal identifier uniquely assigned to thefront seat occupant and a respective stored target height.
 18. Themethod of claim 12 wherein the step of collecting second data iscomprised of capturing an image using an image sensor located at areference position, wherein the image at least partially depicts theD-ring mechanism.
 19. The method of claim 12 wherein the visual guidanceis comprised of a graphic depiction of an action to release the D-ringmechanism for movement.
 20. The method of claim 12 further comprisingthe step of generating an audible cue to the front seat occupant from asound transducer when a manual adjustment of the D-ring mechanism isneeded.